1. Field of the Invention
This invention relates to power transmission belts and, more particularly, to a V-ribbed power transmission belt with a controlled belt slip ratio.
2. Background Art
A conventional V-ribbed belt has a body with an inside and an outside and load carrying members embedded in a cushion rubber layer. A canvas cover is applied on a surface outwardly of the cushion rubber layer, with a plurality of laterally spaced ribs defined on the body inside of the cushion rubber layer. This belt construction has been widely used to drive automobile accessories, such as air compressors, alternators, and the like. For this type of belt to efficiently transmit power to and from cooperating components, it is important to have a relatively low slip ratio between the belt and a cooperating pulley. The belt slip ratio can be decreased by increasing the tension on the belt.
By increasing the tension on the belt, the dry heat shrinkage stress of the belt is increased. However, the dry heat shrinkage ratio and the shrinkage of the belt length over time increase.